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Discussion Starter #1
Based on all the great responses I received yesterday, it is obvious that if I elect to put a even a mild cam in, I need to also install the manufacturers suggested valve springs. I have the motor tore down to the timing chain cover, so now is the time If I'm going to do it. My question is this: Can you install new springs while the heads are still on the motor? Also, never having done this before, are the instructions that come with any given cam going to be sufficient so that I don't cobble up the motor in the process? I'm good with a wrench, but uniformed regarding internal engine work. Thanks!



Shannon a.k.a. The ShanMan!
 

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Yes you can. There is a tool to compress the valve spring when it's on the head. You also need a compressed air source and a compression tester and maybe some adapters. The air will be used to pressurize the cylinder you are working on. This will keep the valves 'up' while you remove and replace the springs, guide seals, etc. It is referred to as a valve spring compressor (on car). Parts stores sell them as well as rent/let you use them, depending on the store.



Steve Leslie, 65 coupe in restoration. 302, toploader, A/C, disc brakes, bench seat
 

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If you cant get the compressed air setup there is an alternative. I have done this twice. Turn the crank so that the piston in the cylinder you will be working on goes down, feed in some rope (some that wont fall apart - as much rope as possible) in through the spark-plug hole of that cylinder, now turn the crank again so that the cylinder comes up. At some point you wont be able to turn any further as the rope is stopping the piston from making it all the way up, now you can safely remove the valve springs with a valve spring compressor without the valves falling in.
Just a word of advice, since you have stripped the engine down do you know when it last had a valve job? If it could use one why not pull the heads off and take them to a machine shop for a valve job and when they reassemble they can put on the new springs and check installed hight etc for you.
When you have the new cam in and are following the instructions to the letter make sure that you alse follow the procedure to the letter in cranking down the rockers again. If you set the wrong preload on any lifter (I guess you are going with hydraulic) then you will end up wiping the cam in no time (been there). Good luck.

69 fastback, 351C, 4spd toploader, restomod BOSS 429 clone, money in the hole........no shame
 

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Just did this 2 weekends ago on my '66. You will find that that certain valve springs are a royal PIA, but it's definately doable. I used the air hose with adapter trick. As far as you've torn the engine down already, the cam itself is a piece of cake.

I highly recommend you go with the recommended valve springs, push rods etc. We fired my high lift cam up with stock rockers, springs and push rods. It took all of about 10 minutes to snap a rocker arm in 2 *LOL*.

If you always do what you've always done,
You'll always get what you've always got
 

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Discussion Starter #5
Are you running stock heads? What cam did you choose?

Shannon a.k.a. The ShanMan!
 

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Yes, currently stock 302 heads. The cam is the Edelbrock Performer RPM cam.

The new plan is to move my 302 heads to my son's '65 coupe project and put 351W heads on my '66.

If you always do what you've always done,
You'll always get what you've always got
 
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